Mini Mill ToolingDrawbarsEnd mill holders, collets, and some drill chucks are held in the spindle by a drawbar. The drawbar extends through the spindle and is tightened from the top of the spindle. Don't tighten the drawbar very tight. It only needs to be snug. If you over tighten the drawbar, it can be very hard to remove Morse taper tooling. R8 tooling is much more forgiving because of the steeper taper. Mini mills from different distributors come with different types of drawbars. All R8 mini mills come with a three-piece drawbar that has a 7/16-20 thread on the end. This drawbar works with any R8 tooling, but it less than convenient because it comprises three pieces: the drawbar, a washer, and a nut. All 3 Morse taper mini mills come with a drawbar with an M12 thread on the end. Grizzly mini mills have a one-piece drawbar, while the others have a three-piece drawbar. Although some 3 Morse taper tooling is available with an M12 drawbar thread, most has a 3/8-16 drawbar thread. Drawbar Options
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